San Diego Bay National Wildlife Refuge: Trails, Wildlife and Access

The refuge has two units, but Sweetwater Marsh has limited visitor access and requires a shuttle ride to its trails.

The U.S. Fish & Wildlife Service identifies Sweetwater Marsh as a place to see coastal salt marshes and intertidal mudflats, habitat that helps support endangered, threatened, migratory and native species. The unit’s listed address is 1080 Gunpowder Point Drive, Chula Vista, CA 91910-8222.

At Sweetwater Marsh, take the free shuttle from the Living Coast Discovery Center to reach the refuge trails. The refuge gives visitor hours as 10 a.m.–5 p.m., Wednesday through Sunday, and says the shuttle runs about every 15 minutes.

Check the official site before you go; the refuge directs visitors to the Living Coast Discovery Center website for current information.

The South San Diego Bay Unit is the refuge’s other area. The two units connect via the Bayshore Bikeway, which gives you a way to travel between them by bike.

Sweetwater Marsh has 1.5 miles of trails where you can walk through protected marsh habitat.

Walking the Sweetwater Marsh trails has no fee, while exploring the Living Coast Discovery Center does have a fee. Keep the distinction in mind when planning: the shuttle serves refuge trail access, and the Discovery Center is a separate paid experience.

Wildlife protection is central to both units. Coastal salt marshes and intertidal mudflats provide habitat for a range of species, including migratory birds and threatened or endangered wildlife. Stay on public trails and observe animals without disturbing them.

Public tours of the South San Diego Bay refuge are available monthly. The San Diego Bird Alliance also leads tours during wintertime; check with the tour organizers for current details before planning around one.

Stay on designated public routes and leave wildlife, plants and habitat undisturbed.

Off-trail activity is prohibited anywhere in the refuge unless the Refuge Manager approves it. Call (619) 221-3473 to request permission. Dogs are not allowed in Sweetwater Marsh; leashed dogs are permitted on the Bayshore Bikeway and other public trails in the South San Diego Bay Unit.

Refuge rules also prohibit camping, open fires, fireworks, hunting, swimming, personal watercraft and water skiing. Horses, ATVs, motorcycles and dirt bikes are not permitted on bike trails or refuge lands.

Do not launch, land or disturb wildlife with aircraft, including drones. The rules also prohibit disturbing or collecting plants or animals, and searching for or collecting artifacts. Keep sound equipment quiet and take all litter with you.

If you’re deciding between the refuge and another outdoor outing, the Kumeyaay Park guide covers a local Chula Vista park.

For the Sweetwater Marsh parking lot and shuttle stop, take the E Street exit from I-5 and turn west where E Street intersects Bay Boulevard.

Once you arrive, use the shuttle from the Living Coast Discovery Center to reach the refuge trails. The refuge’s address for Sweetwater Marsh is 1080 Gunpowder Point Drive in Chula Vista. The Tijuana River National Estuarine Research Reserve visitor guide covers another estuarine reserve.